Serena played spectacular one of her best matches in her career, but I think Safina is a bit slow her game is more suitable to Clay. Serena and Venus always overpowered her on the faster courts look at what Venus did to her in the 2009 Wimbledon Semi Finals 6-1 6-0 and she was ranked number 1 at the time. Her only win against Venus and Serena is on Clay
Safina would have won a grandslam in all probability, only if she would have been fit, injuries followed by the end of 2009 and hampered her career like forever, she tried to make comeback in 2010 but was not successful post that suffering from injuries and not have played professional tennis for three years, she announced her retirement in 2014. Her good year was only 2008, and part of 2009(where she lost many finals), still she was able to reach semifinal stage of All slams, something which even her fellow world no. 1 like wozniacki, ivanovic, jankovic have not done.
I have always felt bad for her. Dementieva, not so much. I also feel Williams gave up GS to a few others, thinking she had time to beat that ugly Court woman.